NEW YORK (Reuters Health) - In untreated patients with hepatitis C virus (HCV) infection cryoglobulinemia does not appear to be a risk factor for peripheral neuropathy, Italian researchers report in the May issue of the Journal of Neurology Neurosurgery and Psychiatry.

Dr. L. Santoro of the University of Naples "Federico II" and colleagues note that HCV may be associated with mixed cryoglobulinemia and a variety of extrahepatic manifestations including peripheral neuropathy. However, the association between cryoglobulinemia and peripheral neuropathy is unclear.

To investigate further, the researchers studied 234 patients at 7 centers. Clinical signs of peripheral neuropathy were seen in 25 (10.6%) and there was subclinical electrophysiological evidence of peripheral neuropathy in a further 11 patients (4.6%).

In all, cryoglobulinemia was found in 56 (29.3%) of 191 tested patients. However, although peripheral neuropathy was seen in 21% of patients with cryoglobulinemia and only 13% of patients without cryoglobulinemia, the difference was not significant.

In fact, peripheral neuropathy increased significantly with age and disease duration. It was present in 4.4% of patients aged less than 45 years compared to 28.1% of those aged 55 to 64 years. Age was the only independent risk factor, with an odds ratio of 1.10 per year.

The researchers note that they are now organizing a prospective study of HCV patients to assess the incidence of neuropathy and the effect of treatment.